Metallurgical furnace.



N o. 699,759. Patented May I3, |902. J. A. HUNTER., mTALLuRGlcAL FuRNAcE.

* (Application filed Aug. 9, 190 O. Renewed Oct, 10, 1901.) (No Model.)

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No. 699.759. Patented May I3', 14902. l

. VJ. A. HUNTER.

METALLURGICAL FUHNACE.

-Appication filed Aug. 9, 1900. Renewed Oct. 10, 1901.)` 1Mo Model.) 2 Sheets-Sheet 2.

a/ma( fvwm ffm ihtrrnn 'raras Aria-1E T JOI'IN A. HUNTER, OF PHILADELPHIA, PENNSYLVANIA.

METALLURGICAL. FURNACE.

SPECIFICATION forming part of Letters Patent No. 699,759, dated May 13, 1902. Application filed August 9, 1900. Renewed October l0, 1901. Serial No. 78,242. (No model.)

Be it known that I, JOHN A. HUNTER, a citizen of the United States, residing in Philadelphia, Pennsylvania, have invented certain Improvements in Metallurgical Furnaces, of which the following is a specification.

My invention relates particularly to metallurgical furnaces intended for the treatment of solid forms of cast-iron for the purpose of converting the same into steel, one object of my invention being to so construct the furnace that it can be readily used either as an open-hearth furnace for the purpose of heating the articles under treat-ment to the desired temperature or as a closed or muftle furnace during the time that such articles are being subjected to the converting treatment.

A further object of the invention is to provide efficient means for introducing and distributing throughout the working chamber of the furnace the agent used for the conversion of the iron.

In the accompanying drawings, Figure l represents a longitudinal section of a furnace constructed in accordance with my invention. Fig. 2 is a transverse section of the same on the line a d, Fig. 1. Fig. 3 is a transverse section on the line b b, Fig. 1; and Fig. 4 is a perspective view, on a larger scale, of a block such as is used in the bottom or iioor of the working chamber of the furnace.

In Figs. 1 and 2 the working chamber of the furnace is shown at l, said furnace having at the rear a fine 2 and at the top a flue 3, communicating with the flue 2 and with the stack et. The working chamber of the furnace' communicates with the rear flue 2 through an opening 5, provided with sliding dampers 0 or other appropriate means whereby communication between the working chamber and the flue 2 through the opening 5 may be permitted or obstructed, as desired, and the flue 2 communicates at its lower end with flues 7 beneath the working chamber of the furnace.

A seriesof gas or oil burners 8 discharges into the Working chamber l through openings in the front wall of the furnace, and a similar burner Ddischarges into the frontend of each of the bottom iiues 7. The body or floor of the working chamber 1 of the furnace is composed of blocks or slabs 10, cach having in the upper surface a recess 1l, so as to leave projecting ribs l2, upon which the articles to be treated are supported. In each block 10, below the recessed portion of the same, is also formed a longitudinal 'opening or channel 13, which communicates with the recess 1l of the block through a series of passages l-i, preferably flared outwardly toward the top and discharging into the recess, and with these channels communicate nozzles 15, projecting from pipes 1G, through which the treating agent is forced or permitted to flow.

A bridge-wall 20 serves to break up and distribute the' liames from the burners 8, so as to cause equal heating of all portions of the charge in the chamber 1.

In operating the furnace the working chamber 1 is first charged with the articles to be treated, and the dampers (5 are opened, so as to provide for a free com munication between said working chamber and the rear iiue 2. A heating-dame is then projected into the working chamber from the burners 8, and this flame is continued until the articles in the working chamber have been raised to the desired temperature, the products of combustion escaping through the opening 5, rear flue 2, and top flue 3, so as toheat the top arch or crown of the furnace and prevent any loss of heat by radiation therefrom. When the articles in the Working chamber have been heated to the desired temperature, the flame from the burners 8 is cut olf, the darnpers G are closed, and flame from the burners 9 is projected into the tlues 7 beneath the floor of the working chamber. This Iiame, after traversing the flues 7, rises through the rear flue 2 and passes again to the front over the top of the furnace through the flue 3, so as to maintain the furnace in a highly-heated condition and prevent rapid loss of heat by the contents of the working chamber. At the same time the treating agent, which may be the gas arising from mixtures such as those described in my Patent No. 600,948, dated March 22, 1898, is forced or permitted to iiow into the channels 13 of the blocks 10, constituting the floor of the working chamber, and passes from these channels through the passages 14. into the recesses 11 of the blocks and thence rises into the working chamber, so as to come into contact with all parts ot' IOC the dampers 6 again closed, and the How of the treating agent into the furnace resumed. By this means I am enabled to quickly change the furnace from an open-hearth into a closed or mufe furnace and I am enabled to effect the distribution of the treating agent th roughout all portions of the working chamber, so that all of the articles contained therein will be uniformly acted upon by said treating agent.

Vhen the blocks l0, constituting the floor of the Working chamber, are long enough to extend completely across the furnace, the partitions separating the flues 7 in the bottom of the furnace will be unnecessary, and a single flue can be used in place of the double flue, and a single burner 8 or 9 may replace the series of burners in furnaces of small size.

Vhen the treating agent is generated in the working chamber of the furnace or is introduced thereinto at some other point than the bottom, said bottom portion of the furnace may simply be provided with ribs, of refractory material, for raising the mass of material to be treated and insuring the access of the treating agent to the under side of said mass.

. The return-flue 3 in the top of the furnace serves to economize the heat by preventing radiation from the top arch or crown of the Working chamber, and the use of this flue is therefore always to be preferred, although it is not absolutely necessary to the broader embodiment of my invention, which contemplates the use ot' a rear chimney or stack communicating directly with the rear flue 2, if desired.

The furnace may also be constructed with a fireplace intended for use of coal, such fireplace communicating through dampered openings with the front end of Ithe Working chamber and with the front end of the flue or flues 7, so that the products of combustion can Y be directed to either working chamber or flues,

as desired.

Having thus described my invention, I

claim and desire to secure by Letters Patent- 1. A metallurgical furnace having a Working chamber, a fine beneath the floor of the same, a discharge-flue communicating with said base-flue, and a dampered opening at that end of the Working chamber, through which said Working chamber communicates with the discharge-flue, and means for supplying heat independently to the Working chamber and the base-tine, substantially as specified.

2. A metallurgical furnace having a Working chamber, a iiue beneath the ioor of the same, a rear tine communicating with said base-flue, and adampered opening at that end of the Working chamber, through Which said Working chamber communicates With the rear flue, a return-flue over the top arch or crown of the Working chamber, and means for supplying h\eat independently to the Working chamberand base-fine, substantially as speci- IIQ.

A metallurgical furnace having a Working chamber with bottom provided with ribs or projections for the support of the material. to be treatedi, means for heating said material by gaseous products of combustion introduced into the working chamber, and provision for introdticing a fluid treating agent into said Working chamber, independently of the gaseous prod ucts ofcombustion,substantially as specified.

4. A metallurgical furnace having a Working chamber, combined with means for introducing gaseous products of combustion into the same and a floor composed of blocks having therein channels or passages for conveying a fluid treating agent into the furnace independently of the gaseous products of combustion, substantially as specified.

5. A metallurgical furnace combined with means for introducing gaseous products of combustion into the same and having a ioor composed of blocks With recessed upper faces, and channels or passages communicating with said recessed faces of the blocks and providing for the introduction of a fluid treating agent into the furnace, independently of the gaseous products of combustion,substantially as specified.

In testimony whereof I have signed my name to this specification in the presence of tWo subscribing witnesses.

JOHN A. HUNTER.

Witnesses:

WILL. A. BARR, Jos. H. KLEIN.

IOO 

